Re: [Mactel-linux-users] lost one cpu core when upgraded to RHEL 5.5

[Justin P. m. <jus...@gm...>]

On 04/13/2010 07:57 AM, Geoffrey wrote:
> Geoffrey wrote:
>> Anyone out there running 64 bit OS on a macbook pro 4,1.  I upgraded
>> from 32 bit Red Hat EL 5.4 to 64 bit RHEL 5.4, then again to 64 bit RHEL
>> 5.5, which is actually still in beta.  I don't know if I lost the core
>> in the 64 bit 5.4 or not.  I see the following from dmesg:
>>
>> SMP: Allowing 2 CPUs, 0 hotplug CPUs
>> .
>> .
>> SMP alternatives: switching to UP code
>> .
>> .
>> SMP motherboard not detected.
>> .
>> .
>> SMP disabled
>
> Thought I'd update the list with a recent success:
>
> For whatever reason, I could not get the initial installation RHEL 5.4
> disk to even boot until I stumbled across a link that suggested the
> following boot parms:
>
> acpi=force noapic irqpoll
>
> I don't know why they worked, but they did.  Once installed, I found
> that I had to add them to my grub.conf to get the install to boot, but
> all was happy.  After moving to 64bit, I lost one core of my two core
> processor.  After much discussion with RH, I revisited these parameters
> and found that by removing the noapic, parm, my macbook would still boot
> and I got both cores.  The weird thing is, I've tried every combination
> of these parms before in order to remove them from my boot process in
> the past, but my macbook would not boot.  There must be something about
> the latest RHEL 5.5 kernel that resolved that issue.
>
> The weird thing is, I did not have this issue on 32bit RHEL 5.4.  That
> is, I had both cores using all these parms.
>

this doesn't seem right..
you need apic etc... they must be
doing something in there configs somewhere
(COFNIG_SMP=y if set gives you both cores
(but could be wrong)).

Justin P. Mattock